Traffic control devices warn vehicle operators of hazards on the non-traffic side of such traffic channelizers. They are also employed for providing temporary delineation and demarcation of traffic lanes in order to guide the flow of traffic through detours, construction areas, and the like.
Traffic channelizers are widely used, and well known in the art, examples being found in such patents as U.S. Pat. No. 4,083,033 and U.S. Pat. No. 4,710,053, the disclosures of which are incorporated by reference herein. They are traffic control devices in the form of barrels or cones, standing as barriers, to discourage crossing the lanes onto the other side thereof. Metallic drums have been employed as traffic channelizers. However to avoid problems which developed during their use, such metal drums have, for the most part, been replaced by plastic traffic channelizers. Present day plastic traffic channelizers are either one-piece traffic control devices, or two-piece channelizing devices, which can be assembled in a stabilized condition at the site.
It has been found that, unlike metal traffic channelizers, some motorists intentionally hit light weight, plastic traffic control elements, knowing that no harm will result to their vehicles. Such impacts displace the channelizers and they must then be returned to their intended location. An advantage of molded plastic traffic control elements is that they can be readily towed or dragged along the ground to return them to their intended location, to place them in a new channelizing location or in a storage area. In addition, some one-piece channelizing devices have open tops which can be readily grasped by an individual when they are moved.
An additional advantage of one-piece traffic control devices is that such channelizing elements, come to rest more predictably near their original channelizing positions, when hit, because of their ballasts. A disadvantage of some one-piece traffic control devices is that they are not easily stackable. Hence they require larger vehicles when they are transported to and from hazard sites. They are bulky and therefore much more inconvenient to move to working areas. In addition if the stabilizing means or ballasts are inaccessibly stored inside them, they are more troublesome to use. Another disadvantage of single piece, or non-breakaway type, channelizing devices is that they may be damaged more extensively on impact than two-piece channelizing devices. Two-piece traffic control elements, on the other hand, are frequently separated on impact by an automobile rather than being damaged by that impact. Another advantage of two-piece traffic control elements is that they can be more readily stacked in a tight nesting relationship for transportation to and from a hazard site.
It can be seen that traffic control elements have been extensively investigated. There are, nevertheless, still areas of improvement, particularly in the stabilization of the traffic control elements with ballasts. Relative to the importance of ballasts, it was pointed out in U.S. Pat. No. 4,710,053, that traffic control elements have a tendency to slide on their supporting surfaces when a gust of wind is suddenly created by a passenger vehicle, truck, or by natural forces. In addition, traffic channelizers utilized on bridge approaches are subject to vibrations caused by the passing motor vehicles causing them to slide from their desired positions.
Normally, ballasts used with traffic control elements have been one or more bags containing a stabilizing material such as sand. In some one-piece traffic control elements, such as cones and the like, the stabilizing material may be closed in, or poured in the unit. But handling and storing problems, already significant, may be multiplied thereby. Two-piece traffic channelizers or open top one-piece traffic control units are preferred because ballasts can be inserted in them during assembly. Even these traffic control elements, however, are subject to improvement. They do not permit the stabilizing material to be spread uniformly across the bottom of the traffic control element. Rather, sandbags confine the stabilizing material so that it cannot be spread across the bottom. Moreover sandbags become lodged against one side of the traffic control element during assembly, or they are thrown against one side on impact. Further, none of the stabilizing materials in use lend themselves to ready disassembly or transportation when the traffic control elements are moved to a new hazardous site. Such shortcomings are overcome by the improvement herein.